Furnace top charging equipment



Dec. 24, 1968 TERUO TSUTSUMI ETAL 3,417,932

FURNACE TOP CHARGING EQUIPMENT Filed Jan. 5, 1966 2 Sheets-Sheet 1 BY g ATTORNEY S 1968 TERUO TSUTSUMI ETAL 3,

FURNACE TOP CHARGING EQUIPMENT Filed Jan. 5, 1966 2 Sheets-Sheet 2 /N VEN 742$ T15R00 sunsQ/M/ /6 7797-500 {4M/704 3404/0/20 A/AGA/ 74 TSU/JK/ W404 BY mgr W ATTORNEYS United States Patent Japan Filed Jan. 3, 1966, Ser. No. 518,179 Claims priority, applicatio'r; Japan, Jan. 7,1965,

4 Claims. (Cl. 26627) ABSTRACT OF THE DISCLOSURE A stationary throttle hopper, provided with a number of rigid rectifying partitions on its inner surface and cooperating with a stationary bifurcated chute and/or with a number of auxiliary hoppers, is centrally arranged above the uppermost bell of a furnace bell hopper system to evenly distribute charging materials poured in said chute or auxiliary hoppers from a conventional transport means.

This invention relates to a furnace-top charging equipment and more particularly to an equipment comprising one or more bell hoppers adapted for successive and uniform charging a blast furnace with material from a conventional conveyor or skip.

The conventional furnace top equipment of blast furnaces that is widely adopted has the structure as shown in FIG. 1 which schematically represents a vertical section of the two-bell type furnace top charging equipment with a hoisting skip.

The charging materials which are poured from the skip (g) at a definite position through the stationary hopper (f) are stored up in the small bell hopper (c) and, after the position of the top of the unevenly piled-up material (1') is uniformly distributed by intermittently rotating the small bell (e) and the small bell hopper (c) (this method is usually called the six-point distribution method, and the angles of rotation are 60, 120, 180, 240, 300, and 360), the small bell (e) is opened in order to pour the materials onto the large bell (d). Then the small bell (e) is closed while the large bell (d) is opened so as to pour the materials into the furnace (a) whereas the gas in the furnace (a) being prevented from leaking into the air.

However, the furnace top charging equipment of this type has following kinds of disadvantages:

(i) For the rotation of the small bell (e) and the small bell hopper (c), a gas-sealing device is required between the stationary part and the rotary part; usually it is a grease seal device that is adopted for this purpose. However, the latter device not only has difficulty in uniformly sealing the long periphery of the both parts but also requires a great amount of grease and consumes much electric power for its operation.

(ii) Since the time of respective angular movements, i.e., 60, 120, 180, 240, 300, and 360 (0), is very different from the preceding one, a complex limit switch is required as well as control devices such as a dynamic brake for rising the accuracy in stopping the rotation.

(iii) For carrying out said rotation, a gear (j) having a long diameter, rollers (k), (l), (m), a reduction gear, etc., all adapted to withstand for a long period of use an unsuitable atmosphere with abundant dust, are required.

(iv) Since the bells must perform two functions, as the channel for pouring the materials and as the valves to prevent the leakage of gas from the furnace, the surface of the bells is so worn out by the flow of the materials that it soon becomes unable to function as a valve. The result is that the gas flows on the sealing part of the bell, the dust 3,417,982 Patented Dec. 24, 1968 in the gas quickening the abrasion On the surface of the bells. In particular, the small bell (e) whose diameter is smaller than that of the large bell (d) is subject to increased abrasion on the surface caused by the flow of the materials, and it will have only a short span of life.

Therefore, the primary object of this invention is to provide a uniform distribution of charging material within the bell hoppers.

Another object of this invention is to eliminate rotation of the small bell hopper and thereby to eliminate use of the grease seal device.

Further object of this invention is to reduce abrasion of the surface of the small bell.

Still further object of this invention is to provide a furnace-top charging device which is durable and low in cost.

An embodiment of this invention will be explained with reference to the accompanying drawings wherein FIGS. 2 through 5 illustrate the preferred embodiments of the furnace top charging equipment of the present invention.

FIG. 6 shows the cross section seen in the direction of A in FIG. 2.

FIG. 7 and FIG. 8 show the cross-sectional views along lines in directions of B and C in FIG. 3, respectively.

FIG. 9 and FIG. 10 show the cross-sectional views along lines in directions of D and E in FIG. 4, respectively.

In the drawings, 1 refers to the inside of the furnace, 2 to the large bell hopper, 3 to the small bell hopper, 4 to the throttle hopper, 5 to the large bell, 6 to the small bell, 7 to the rectifying partition, 8 to the bifurcated chute, 9 to the charging materials, 10 to the conveyer for charging the materials, 11 to the furnace top seal valve, 12 to the skip car, 13 to the auxiliary hopper, 14 to the hopper gate, 15 the upper auxiliary hopper, and 16 to a lower auxiliary hopper, respectively.

FIG. 2 shows an application of the present invention to a conveyor type furnace top charging equipment with a two bell hopper system comprising large bell hopper 2 with large bell 5 and stationary small bell hopper 3 with small bell 6. According to this invention, a stationary throttle hopper 4 is installed under the bifurcated chute 8 at the end of the conveyor 10, the said hopper 4 being fixed to the upper end of th stationary small bell hopper 3. The effect of the distribution of the materials can be improved, if necessary, by installing rectifying partitions 7 on the lower part of the throttle hopper 4 as it is shown in FIG. 6.

The materials 9 after having been hoisted up by the charging conveyor 10 and divided into two streams by the bifurcated chute 8 which is located at the end of the said conveyor 10, fall onto the throttle hopper 4, and after being rectified by the rectifying partitions 7 and the central mouth of the throttle hopper 4 at its lower end, are poured evenly onto the small bell 6 so that they are uniformly distributed thereupon. After a definite amount (corresponding to a skipful of materials) of the materials has been uniformly piled-up, the small bell 6 is opened to pour the materials onto the large bell 5, the small hell 6 being closed successively.

The above described charging and rectifying operation is repeated until large bell 5 is supplied with the required amount of material. Subsequently, large bell 5 is opened and materials are fed into furnace 1.

FIG. 3 shows an example of the application of the present invention to the conventional skip type furnace top charging equipment. In this example, there is employed a large bell 5 only whereas the small bell is replaced by furnace top seal valves 11.

The throttle hopper 4 is attached directly to a stationary gas-tight receptacle on the large bell hopper 2, and

the outlet of the hopper 4 is directed against the vertex of the large bell 5. To assure an even distribution of charging material, two auxiliary hoppers 13 are installed side by side on the sealed top portion of the throttle hopper 4. Each of said auxiliary hoppers 13 is provided at its outlet with a furnace seal valve 11 which performs the gassealing function instead of small bell. The open top portion of each hopper 13 is located beneath discharging site of skip cars 12.

Prior to pouring out material from respective skips 12 into auxiliary hoppers 13, the valves 11 are first fully opened.

Subsequently, material from one skip 12 is poured out and passes through one of said hoppers 13 into the throttle hopper 4. Due to the reduced outlet of the hopper 4, material 9 falls therethrough in a uniform vertical stream and is evenly distributed about the center of the large bell 5. Immediately after emptying of the auxiliary hopper 13, the valve 11 is closed again. In the same manner the above described discharging and material distributing process is carried out with material from the second skip 12 and, as soon as materials from the both skips 12 are stored up on the large bell 5, the latter is opened and furnace 1 is charged.

Another modification of the embodiment of FIG. 3 is shown in FIG. 4 in connection with a conveyor type furnace charging equipment. Each auxiliary hopper in this embodiment is represented by a combination of a lower stationary hopper 16 having the seal valve 11 and an upper stationary hopper 15 being provided with a hopper gate 14. A bifurcated chute 8 is disposed above respective upper hoppers 15 to store the charging material from a conveyor 10. The amount of material stored within each upper hopper 15 is equivalent to one half of a skipful applied to in case of skip-type charging. Subsequently, the two furnace top seal valves 11 and the two hopper gates 14 are simultaneously opened and charging material passes through the throttle hopper 4 in the same way as in FIG. 3.

In FIG. 5, it is shown a further variation of the charging equipment of FIG. 4. A small bell 6 with corresponding small bell hopper is installed between the throttle hopper 4 and the large bell hopper 2. Due to the action of furnace top seal valves 11, this structure has the same effect as the conventional three bell type furnace top charging equipment.

The effects of the furnace top charging equipment of the present invention are as follows:

(I) Since the rotary mechanism has been dispensed with by the fixing of the small bell hopper and by the installation of the throttle hopper above the small bell, the grease seal is not necessary any more. Hence there is no worry about possible leakage of gas at the grease sealed parts and no grease will be consumed for sealing.

(II) Since we do not revolve the small bell hoppers, we need no reduction gear including the revolutionary ring gear, no electric motor, and no control device any longer. Hence a considerable saving in the cost of equipment can be achieved.

(III) Since expenses on the electric power for driving the revolving mechanism is not necessary, the running cost can be reduced.

(IV) Since time for revolution is not required, the hoisting time schedule can be shortened, hence increasing the hoisting capacity.

(V) Since we have replaced the small bell part by the furnace top seal valve wherein the valve seat does not touch the materials and the valve disk can be evacuated from the passage of the materials, the sealing parts do not sutfer from possible abrasion caused by the flow of the materials.

(VI) Since the sealing part of the said furnace top seal valve does not touch the materials, we can have gas completely sealed by means of elastic materials such as rubber, for example. Consequently it does not suffer from abrasion due to the gas which includes dusts.

(VII) Since the furnace top seal valve is of small size and receives no load of the materials, the opening and closing mechanism, and the driving power require extremely less compared with the conventional small bell.

What we claim is:

1. A furnace-top charging equipment provided with a bell hopper arrangement for successively charging a blast furnace with material delivered from conventional material transport means, comprising a stationary throttle hopper installed in a gas-tight manner above the uppermost bell in said bell hopper arrangement and fixed thereto, said throttle hopper having a central mouth and rectifying means in the form of substantially V-shaped slits located on opposite sides of said central mouth, stationary means for distributing said charging material to fall from a number of spaced outlets into said throttle hopper, said material passing through said central mouth and rectifying means to fall in a uniform vertical stream onto a central area of said bell.

2. The furnace-top charging equipment as claimed in claim 1 further comprising a bifurcated chute adapted to receive said material from said conveyor means and to distribute through respective legs thereof the received material on different areas within said throttle hopper a number of auxiliary hoppers mounted in gas-tight relationship on the top portion of said throttle hopper, each of said auxiliary hoppers being located beneath a respective leg of said chute to receive the charging material and having a controllable seal valve at its outlet to said throttle hopper.

3. The furnace-top charging equipment as claimed in claim 2 further comprising a bifurcated chute adapted to receive said material from said conveyor means and to distribute through respective legs thereof the received material on difierent areas Within said throttle hopper a number of storage hoppers mounted on respective top portions of said auxiliary hoppers, each of said storage hoppers being located beneath a respective leg of said chute to receive the charging material and having a hopper gate at its outlet to said auxiliary hopper.

4. The furnace-top charging equipment as claimed in claim 1 comprising skip means for discontinuous delivering the charging material, a number of auxiliary hoppers mounted on the top portion of said throttle hopper, the outlets of respective auxiliary hoppers being provided with controllable seal valves and the inlets of said auxiliary hoppers being adapted for receiving material from said skip means.

References Cited UNITED STATES PATENTS 3,131,821 5/1964 Tsujihata et a1 26627 X 3,297,432 1/ 1967 Mohr 26627 X FOREIGN PATENTS 1,081,972 12/1954 France.

14,544 3/1956 Germany.

OTHER REFERENCES Modern Castings, July 1960, pp. 32-33.

WILLIAM J. STEPHENSON, Primary Examiner.

EUGENE MAR, Assistant Examiner.

U.S..Cl. X.R. 214-36 

